Final answer:
Wave-particle duality does not apply to macroscopic objects, gravity can bend light despite it having no rest mass, and the photoelectric effect can be caused by various types of electromagnetic radiation, not just visible light.
Step-by-step explanation:
The concept of wave-particle duality states that every particle or quantum entity can exhibit both wave and particle characteristics. However, this concept is typically not observable on a macroscopic scale, thus the statement that wave-particle duality exists for macroscopic objects is false.
When considering the interaction of light with matter, a photon, which exhibits characteristics as a particle or a wave, indeed has no rest mass. Nonetheless, Einstein's theory of General Relativity explains that gravity can bend light, which is an effect observed during a phenomenon such as gravitational lensing. Therefore, the statement that gravity bends a beam of light is true.
In the context of the photoelectric effect, it is true that a current is generated in a photoconductive cell even if only one electron is expelled due to a photon strike. Furthermore, the photoelectric effect is not limited to visible light; other forms of electromagnetic radiation can also induce this effect, making the statement that only visible light can cause the photoelectric effect false.
Regarding high-voltage power transmission, the statement that the wires are wrapped in an insulating material is false. These high-voltage wires are commonly held aloft by insulating connectors but are not wrapped in insulation due to practicality and efficiency reasons.